The present invention is related to an improvement in a pawl construction and mounting means therefor for use in controlling the operation of a hand operated winch.
A double-acting pawl and ratchet arrangement having three positions corresponding to forward, reverse and free-running movement of the winch is well known in the prior art. In one known construction, the pawl includes two gear-engaging teeth alternately engageable with a driving gear for permitting the gear to be rotated either clockwise or counterclockwise depending on which of the pawl teeth is engaged against the driving gear. Integrally connected with the teeth of the pawl is a handle for operating the pawl to move the teeth into and out of engagement with the driving gear. A spring having cam surfaces is provided adjacent the pawl and engages with two cam followers rigidly connected to the pawl in order to maintain the pawl in a fixed position. When one of the two pawl teeth engages against the driving gear, the winch may be operated only in the forward direction; when the other of the two teeth engages against the driving gear, the winch is operable only in the reverse direction; and when the pawl is pivoted into neutral position, the winch can be operated freely in either the forward or reverse direction.
While the ratchet and pawl arrangement of the prior art is generally effective for its intended purpose of governing the operation of the winch, it does have some drawbacks. For example, problems result from the relatively high mass of the pawl which includes the engaging teeth, connecting members, cam followers, and a handle portion which extends outwardly away from the engaging teeth. The relatively high mass of this pawl results in a rougher and more discontinuous operation than is desirable since, with high speed gear travel, the inertia of the pawl prevents it from closely following the driving gear. Also, the high mass of the pawl results in higher acoustical noise levels than those produced by the pawl of the present invention.
Another disadvantage of this pawl is that it can be unintentionally disengaged from the driving gear of the winch. When a sufficient force is exerted by the pawl, the cam followers sometimes ride out of the desired location against the cams. Having moved into the new location, the cams and cam followers tend to hold the pawl in this location, thus requiring the manual re-engagement of the pawl. Likewise, when the pawl is in the neutral, free-running position, permitting the winch to be operated in the forward or reverse direction, it can be accidentally engaged, possibly causing damage to the winch gears and/or the pawl.